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front anit-roll bar?
darren(SA) - 1/5/02 at 09:07 AM

Hi there guys,

We've just finished putting the front suspension on , and were just wandering about a anti roll bar. How do I go about sorting this out? Is there a car which has a suitable one to use?

please bear in mind that I'm in South Africa

thanks guys!

darren


interestedparty - 1/5/02 at 09:57 AM

Are you sure you need one, most seven-style car owners don't bother. I doubt if any production car AR bar would suit anyway, the rate would be much too high for a light car with low CG, and most of them are bent to suit a specific fit. If you decide you need one you need to look at the sort of thing fitted to race cars, with clamps that can be slid along and locked to adjust the AR stiffness.
John


Dunc - 1/5/02 at 10:16 AM

The use of an antiroll bar is used on cars with poor suspension setup. ie most production cars. The ideal setup is to have the roll axis set slightly below the C' of G'. You could have the roll axis go through the C' of G' and have no roll at all but it does make bumps more harsh. Production cars tend to have the roll centre set between the ground and the sump, but it can be below the ground but you don't want it too great as the rolling torque increases the further away from the roll C' of G' you get. That old Force x Radius formula again.

If you fit too strong a roll bar, like those on most 4x4's, Troopers etc, then the side effects are violent sideways motions of the head when you hit a bump. If you haven't noticed it before in one of these you will now.

If you do fit an antiroll bar it is easy enough to make, just bend a solid bar of metal into your the shape you want then fit a couple of off the shelf tie bars or rose jointed rods and connect to the plate on the lower wishbone that the lower shock mount is welded to. But do make sure first that the full motion of the wheels steering and shocks don't interfere with it.

Dunc.


darren(SA) - 1/5/02 at 05:44 PM

what you guys are saying, makes a lot of sense. I've seen anti-roll bars on quite a few 7's and I thought it was just a standard thing.

But at the same time, this should improve the handling (depending on the thickness of the bar) right?

Well, I'll leave it for now and If I really need it afterwards, It shouldn't be too much hassle fitting one.

thanks guys!

darren